This is a multicenter Phase III blinded, randomized study, to evaluate the efficacy and safety of two dose levels of DAB389IL-2 (9 and 18 ug/kg) in CTCL patients with Stage Ib-III disease who, following at least 4 previous therapies or Stage IVa disease following at least 1 previous therapy, have recurrent or persistent disease. Patients will be randomized to one of two treatment arms (9 or 18 ug/kg/day) in a blinded fashion.